For integrally molding a labeled resin container, a process has been used which comprises inserting a blank or label into a mold beforehand and then molding a container in the mold by injecting molding, blow molding, pressure-difference molding, foam molding, or the like to label the container for decoration, etc. (see JP-A-58-69015 and EP-A-254,923). Known labels for use in such in-mold forming include labels comprising a resin film printed by gravure printing, labels comprising a synthetic paper printed by multicolor offset printing (see, for example, JP-B-2-7814 and JP-A-2-84319), and aluminum labels obtained by laminating a high-pressure-process low-density polyethylene or an ethylene/vinyl acetate copolymer to the back side of an aluminum foil and printing the front side of the foil by gravure printing.
In recent years, recycling techniques contributing to environmental conservation are attracting attention. Under these circumstances, when only the resinous container components after the molding or after the contents have been used up are recycled in the in-mold forming, it is necessary to conduct the step of stripping off the labels at a high temperature (hereinafter referred to as delabeling). Labels employing branched low-density polyethylene as a heat-sealable resin have relatively satisfactory adhesion between the label and the container. However, when it is attempted to strip off these labels at a high temperature, the labels remain on the containers. Namely, these labels have poor suitability for delabeling. On the other hand, labels employing an ethylene/vinyl acetate copolymer or ethylene/acrylic acid copolymer having a low melting point as a heat-sealable resin have a problem that this resin has poor heat resistance and, hence, plated inner surfaces of the extruder and dies corrode.